R v Sang (R v Mangan)

Entrapment is not a defence in English criminal law. A person who intentionally commits an offence remains guilty although a police officer or informer induced its commission. The inducement may mitigate sentence, but it cannot justify excluding the prosecution evidence so as to secure an acquittal.

A criminal court may exclude admissible evidence where its prejudicial effect outweighs its probative value. Apart from admissions, confessions and, generally, post-offence evidence obtained from the accused, relevant admissible evidence cannot be excluded merely because it was obtained improperly or unfairly. The court controls the use of evidence at trial; it does not discipline the police through evidential rulings.

R v Sang was charged at the Central Criminal Court with conspiracy to utter counterfeit American banknotes. Before trial, he alleged that a police informer had induced him to commit an offence which he would not otherwise have committed. He submitted that the judge should determine that allegation in a trial within a trial and, if satisfied, exclude the prosecution evidence.

Judge Buzzard ruled that he had no discretion to exclude relevant admissible evidence on that basis. The appellant then withdrew his plea of not guilty, pleaded guilty and received 18 months' imprisonment. The Court of Appeal (Criminal Division) dismissed his appeal.

The House considered whether evidence could be excluded because an offence had been instigated by an agent provocateur. It also addressed the wider certified question whether a criminal trial judge may refuse evidence, other than an admission, which is relevant and has more than minimal probative value.

1. Appeal dismissed unanimously. Per Lord Diplock, in the leading speech, the decisions that entrapment is not a defence were correct. Viscount Dilhorne, Lord Salmon, Lord Fraser of Tullybelton and Lord Scarman reached the same conclusion. An accused who intentionally performs the physical elements of an offence possesses both the actus reus and mens rea. The identity of the person who counselled or procured the offence does not alter guilt.

2. The trial judge could not exclude the evidence merely because the offence was assumed to have been instigated by a police informer. Such exclusion would create, by procedural means, a discretionary defence of entrapment. It would allow the judge to secure an acquittal despite proof of guilt and would usurp the functions of the substantive criminal law and, on indictment, the jury. Official inducement may instead be relevant to sentence.

3. Per Lord Diplock, in the answer accepted by the other Law Lords, a criminal court has a discretion to exclude admissible evidence where its prejudicial effect outweighs its probative value. The principle applies both to a judge sitting with a jury and to magistrates. Its purpose is to protect the fairness of the trial.

4. Except in relation to admissions, confessions and, generally, post-offence evidence obtained from the accused, there is no discretion to exclude relevant admissible evidence merely because it was obtained improperly or unfairly. The court is concerned with the use of evidence at trial, rather than the manner in which investigators obtained it. Police illegality may attract civil remedies, and breaches of police standards may attract disciplinary action, but those matters do not themselves justify exclusion.

5. Reg. v. Ameer and Lucas [1977] Crim.L.R. 104 was wrongly decided. In so far as Reg. v. Murphy [1965] N.I. 138 suggested that agent-provocateur evidence could be excluded on that ground, it was no longer to be regarded as good law.

6. Lord Salmon and Lord Scarman expressly regarded the discussion extending beyond entrapment as obiter. They emphasised the general duty to secure a fair trial, while accepting that the discretion could not be used to create an entrapment defence or to control the police and prosecuting authority.

1. House of Lords: The appeal in R v Sang [1980] AC 402 was dismissed unanimously. The House upheld the ruling that the prosecution evidence could not be excluded because the offence had allegedly been induced by an agent provocateur.
2. Court of Appeal (Criminal Division): The appellant's appeal from Judge Buzzard's ruling was dismissed. The court certified a general question concerning the discretion to exclude relevant evidence of more than minimal probative value.
3. Central Criminal Court: Judge Buzzard ruled that the alleged inducement by a police informer did not permit exclusion of the prosecution evidence. The appellant then pleaded guilty and was sentenced to 18 months' imprisonment.